Promising Way (promising + way)

Distribution by Scientific Domains


Selected Abstracts


Market-based grid resource co-allocation and reservation for applications with hard deadlines

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 18 2009
Kurt Vanmechelen
Abstract Grid computing technology enables the creation of large-scale IT infrastructures that are shared across organizational boundaries. In such shared infrastructures, conflicts between user requirements are common and originate from the selfish actions that users perform when formulating their service requests. The introduction of economic principles in grid resource management offers a promising way of dealing with these conflicts. We develop and analyze both a centralized and a decentralized algorithm for economic grid resource management in the context of compute bound applications with deadline-based quality of service requirements and non-migratable workloads. Through the use of reservations, we co-allocate resources across multiple providers in order to ensure that applications finish within their deadline. An evaluation of both algorithms is presented and their performance in terms of realized user value is compared with an existing market-based resource management algorithm. We establish that our algorithms, which operate under a more realistic workload model, can closely approximate the performance of this algorithm. We also quantify the effect of allowing local workload preemption and different scheduling heuristics on the realized user value. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Surgery for Ruptured Sinus of Valsalva Aneurysm into Right Ventricular Outflow Tract: Role of Intraoperative 2D and Real Time 3D Transesophageal Echocardiography

ECHOCARDIOGRAPHY, Issue 7 2010
Shrinivas Gadhinglajkar M.D.
A major limitation of the 2D echocardiography during surgery for a complex cardiac lesion is its inability to provide an accurate spatial orientation of the structure. The real time 3D transesophageal echocardiography (RT-3D-TEE) technology available in Philips IE 33 ultrasound machine is relatively new to an operation suite. We evaluated its intraoperative utility in a patient, who was operated for repair of a ruptured sinus of Valsalva aneurysm (RSOVA) and closure of a supracristal ventricular septal defect. The VSD and RSOVA were visualized through different virtual windows in a more promising way on intraoperative RT-3D-TEE than on the 2D echocardiography. The acquired images could be virtually cropped and displayed in anatomical views to the operating surgeon for a clear orientation to the anatomy of the lesion. RT-3D-TEE is a potential intraoperative monitoring tool in surgeries for complex cardiac lesions. (Echocardiography 2010;27:E65-E69) [source]


Protocols and techniques for a scalable atom,photon quantum network

FORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 11-12 2009
L. Luo
Abstract Quantum networks based on atomic qubits and scattered photons provide a promising way to build a large-scale quantum information processor. We review quantum protocols for generating entanglement and operating gates between two distant atomic qubits, which can be used for constructing scalable atom,photon quantum networks. We emphasize the crucial role of collecting light from atomic qubits for large-scale networking and describe two techniques to enhance light collection using reflective optics or optical cavities. A brief survey of some applications for scalable and efficient atom,photon networks is also provided. [source]


Sensing of Damage Mechanisms in Fiber-Reinforced Composites under Cyclic Loading using Carbon Nanotubes

ADVANCED FUNCTIONAL MATERIALS, Issue 1 2009
Limin Gao
Abstract The expanded use of advanced fiber-reinforced composites in structural applications has brought attention to the need to monitor the health of these structures. It has been established that adding carbon nanotubes to fiber-reinforced composites is a promising way to detect the formation of microscale damage. Because carbon nanotubes are three orders of magnitude smaller than traditional advanced fibers, it is possible for nanotubes to form an electrically conductive network in the polymer matrix surrounding the fibers. In this work, multi-walled carbon nanotubes are dispersed into epoxy and infused into a glass-fiber preform to form a network of in situ sensors. The resistance of the cross-ply composite is measured in real-time during incremental cyclic tensile loading tests to evaluate the damage evolution and failure mechanisms in the composite. Edge replication is conducted to evaluate the crack density after each cycle, and optical microscopy is utilized to study the crack mode and growth. The evolution of damage can be clearly identified through the damaged resistance parameter. Through analyzing the damaged resistance response curves with measurements of transverse crack density and strain, the transition between different failure modes can be identified. It is demonstrated that the integration of an electrically conducting network of carbon nanotubes in a glass fiber composite adds unique damage-sensing functionality that can be utilized to track the nature and extent of microstructural damage in fiber composites. [source]


The Impact of Increased Fees on Participation in Higher Education in England

HIGHER EDUCATION QUARTERLY, Issue 2 2005
Hazel Pennell
This article explores some recent research evidence on the possible impact of the higher education reforms in England on participation by students from lower socio-economic backgrounds. The evidence is examined in terms of costs, debt and term-time working. Financial issues have been shown to constrain choice of institution and place of study for lower-income students, and financial problems are commonly cited as reasons for dropping out of higher education. The greatest difference in debt levels has been found to be linked to family background, with students who were poor before they entered university leaving university with the largest debts. Overdrafts and credit card debt levels have been shown to be lower for students in receipt of grants than for those who are not. Research has shown that school leavers who are least debt-averse are more likely to go to university than those who are anti-debt; the latter include those from the lowest socio-economic groups and certain black and minority ethnic groups. Students who work in term-time may achieve less academically: those who work in term-time are more often those from lower socio-economic groups or minority ethnic groups. Overall, the evidence indicates that financial payments and grants are likely to be the most promising way forward to increase participation in higher education among those from lower socio-economic backgrounds. [source]


GENOMIZER: an integrated analysis system for genome-wide association data,

HUMAN MUTATION, Issue 6 2006
Andre Franke
Abstract Genome-wide association analysis appears to be a promising way to identify heritable susceptibility factors for complex human disorders. However, the feasibility of large-scale genotyping experiments is currently limited by an incomplete marker coverage of the genome, a restricted understanding of the functional role of given genomic regions, and the small sample sizes used. Thus, genome-wide association analysis will be a screening tool to facilitate subsequent gene discovery rather than a means to completely resolve individual genetic risk profiles. The validation of association findings will continue to rely upon the replication of "leads" in independent samples from either the same or different populations. Even under such pragmatic conditions, the timely analysis of the large data sets in question poses serious technical challenges. We have therefore developed public-domain software, GENOMIZER, that implements the workflow of an association experiment, including data management, single-point and haplotype analysis, "lead" definition, and data visualization. GENOMIZER (www.ikmb.uni-kiel.de/genomizer) comes with a complete user manual, and is open-source software licensed under the GNU Lesser General Public License. We suggest that the use of this software will facilitate the handling and interpretation of the currently emerging genome-wide association data. Hum Mutat 27(6), 583,588, 2006. © 2006 Wiley-Liss, Inc. [source]


Sintered Reaction-Bonded Silicon Nitride with High Thermal Conductivity and High Strength

INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 2 2008
You Zhou
Sintered reaction-bonded silicon nitride (SRBSN) materials were prepared from a high-purity Si powder doped with Y2O3 and MgO as sintering additives by nitriding at 1400°C for 8 h and subsequently postsintering at 1900°C for various times ranging from 3 to 24 h. Microstructures and phase compositions of the nitrided and the sintered compacts were characterized. The SRBSN materials sintered for 3, 6, 12, and 24 h had thermal conductivities of 100, 105, 117, and 133 W/m/K, and four-point bending strengths of 843, 736, 612, and 516 MPa, respectively. Simultaneously attaining thermal conductivity and bending strength at such a high level made the SRBSN materials superior over the high-thermal conductivity silicon nitride ceramics that were prepared by sintering of Si3N4 powder in our previous works. This study indicates that the SRBSN route is a promising way of fabricating silicon nitride materials with both high thermal conductivity and high strength. [source]


Polybenzimidazole-Based Membranes as a Real Alternative to Nafion for Fuel Cells Operating at Low Temperature,

ADVANCED MATERIALS, Issue 7 2008
Piercarlo Mustarelli
Filler up! Composite proton-conducting membranes, based on polybenzimidazole (PBI) and imidazole-derivatized silica are presented. The addition of even small amounts (,10 wt %) of filler causes an outstanding improvement in the permanent proton conductivity by a factor <103. The preparation of PBI composite membranes with basic functionalities is a promising way to make possible their use in PEMFCs operating around 120,°C, that is, the temperature required for automotive applications. [source]


Properties of soy protein isolate/poly(vinyl alcohol) blend "green" films: Compatibility, mechanical properties, and thermal stability

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008
Jun-Feng Su
Abstract Blend films from nature soy protein isolates (SPI) and synthetical poly(vinyl alcohol) (PVA) compatibilized by glycerol were successfully fabricated by a solution-casting method in this study. Properties of compatibility, mechanical properties, and thermal stability of SPI/PVA films were investigated based on the effect of the PVA concentration. XRD tests confirm that the SPI/PVA films were partially crystalline materials with peaks of 2, = 20°. And, the addition of glycerol will insert the crystalline structure and destroy the blend microstructure of SPI/PVA. Differential scanning calorimetry (DSC) tests show that SPI/PVA blend polymers have a single glass transition temperature (Tg) between 80 and 115.0°C, which indicate that SPI and PVA have good compatibility. The tension tests show that SPI/PVA films exhibit both higher tensile strength (,b) and percentage elongation at break point (P.E.B.). Thermogravimetric analysis (TGA) and water solubility tests show that SPI/PVA blend polymer has more stable stability than pure SPI. All the results reflect that SPI/PVA/glycerol blend film provides a convenient and promising way to prepare soy protein plastics for practical application. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source]


Release of gentamicin from bone regenerative materials: An in vitro study

JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007
M. Teller
Abstract Antibiotic loading of bone regenerative materials is a promising way to protect augmentation procedures from infection during the resorption phase of bone substitutes. Especially in the early stage of implantation, it should protect the grafted site against microbiological pathogens. The present study reports the release kinetics of gentamicin after loading from two synthetic bone filling materials. The first, BONITmatrix®, is a biphasic calcium phosphate silica composite obtained by the sol,gel route consisting of 13% silicon dioxide (w/w) and calcium phosphates (hydroxyapatite/,-tricalcium phosphate 60/40 w/w). The second, Synthacer®, is a sintered hydroxyapatite ceramic. Gentamicin was loaded by dipping and by vacuum coating. Release kinetics of the loaded Gentamicin was investigated by fluorescence polarization immunoassay and by staphylococcus aureus assay. By dipping, loading failed for Synthacer, and it was 12.7 mg gentamicin per gram bone substitute for BONITmatrix. By vacuum coating, loading was 11.3 mg gentamicin per gram bone substitute for Synthacer and 7.4 mg gentamicin per gram bone substitute for BONITmatrix. Distinct release kinetics were measured. For Synthacer, a high initial release was followed by a lower protracted release level up to 28 days. For BONITmatrix release was continuous over the investigated 70-day period. The present data suggest that the porosity properties at the nano- and microscopic levels, or the composition are responsible for antibiotic loading and subsequent release. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source]


Health Insurance Literacy of Older Adults

JOURNAL OF CONSUMER AFFAIRS, Issue 2 2009
LAUREN McCORMACK
We developed an instrument to measure dimensions of health insurance literacy reflecting familiarity with health insurance terminology and proficiency with the Medicare program. The instrument's items were based on a conceptual framework integrating the financial and health insurance literacy fields and were fielded in a national survey of older adults. We found that overall levels of health insurance literacy were low to moderate. The oldest adults, those with lower education and income, and those with poorer health had lower levels of health insurance literacy. The items demonstrated good psychometric properties and construct validity. They are a promising way to measure selected aspects of health insurance literacy. [source]


Harnessing experience: exploring the gap between evidence-based medicine and clinical practice

JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 5 2008
M. Cameron Hay PhD
Abstract Rationale, aims and objectives, There is mounting evidence of a gap between Evidence-based Medicine (EBM) and physician clinical practice, in part because EBM is averaged global evidence gathered from exogenous populations which may not be relevant to local circumstances. Local endogenous evidence, collected in particular and ,real world' patient populations may be more relevant, convincing and timely for clinical practice. Evidence Farming (EF) is a concept to provide such local evidence through the systematic collection of clinical experience to guide more effective practice. Methods, We report on the findings of a pilot study of 29 individual and three focus group (n = 10) interviews exploring physicians' evaluations how they use multiple sources of information in clinical decision making and their thoughts on EF. Results, Physicians recognize a gap in translating EBM to practice. Physicians reported that when making clinical decisions, they more often rely on clinical experience, the opinions of colleagues and EBM summarizing electronic clinical resources rather than refer directly to EBM literature. Confidence in making decisions based on clinical experience increases over time, yet few physicians reported having systems for tracking their clinical experience in designing treatment plans and patient outcomes. Most physicians saw EF as a promising way to track experience, thereby making scientific evidence more relevant to their own clinical practices. Conclusion, Clinical experience is relatively neglected by the EBM movement, but if that experience were systematically gathered through an approach such as EF, it would meet a need left unfulfilled by EBM. [source]


Design of improved permeation enhancers for transdermal drug delivery

JOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2009
Srinivas S. Godavarthy
Abstract One promising way to breach the skin's natural barrier to drugs is by the application of chemicals called penetration enhancers. However, identifying potential enhancers is difficult and time consuming. We have developed a virtual screening algorithm for generating potential chemical penetration enhancers (CPEs) by integrating nonlinear, theory-based quantitative structure,property relationship models, genetic algorithms, and neural networks. Our newly developed algorithm was used to identify seven potential CPE molecular structures. These chemical enhancers were tested for their toxicity on (a) mouse embryonic fibroblasts (MEFs) with MTT assay, and (b) porcine abdominal skin by histology using H/E staining at the end of a 48-h exposure period to the chemicals. Further, melatonin permeability in the presence of the enhancers was tested using porcine skin and Franz diffusion cells. Careful toxicity tests showed that four of the seven "general" CPEs were nontoxic candidate enhancers (menthone, 1-(1-adamantyl)-2-pyrrolidinone, R(+)-3-amino-1-hydroxy-2-pyrrolidinone, and 1-(4-nitro-phenyl)-pyrrolidine-2,5-dione). Further testing of these four molecules as potential melatonin-specific CPEs revealed that only menthone and 1-dodecyl-2-pyrrolidinone provided sufficient enhancement of the melatonin permeation. The results from our permeability and toxicity measurements provide validation of the efficacy and ability of our virtual screening algorithm for generating potential chemical enhancer structures by virtual screening algorithms, in addition to providing additional experimental data to the body of knowledge. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4085,4099, 2009 [source]


Improvement of dissolution and oral absorption of ER-34122, a poorly water-soluble dual 5-lipoxygenase/cyclooxygenase inhibitor with anti-inflammatory activity by preparing solid dispersion

JOURNAL OF PHARMACEUTICAL SCIENCES, Issue 1 2002
Ikuo Kushida
Abstract Several formulation approaches were attempted to improve the dissolution and the oral absorption of ER-34122, which is a novel dual 5-lipoxygenase/cyclooxygenase inhibitor with potent anti-inflammatory activity. The solid dispersion of ER-34122 with hydroxypropylmethylcellulose (TC-5RW), which is an inert solid carrier, resulted in a significant improvement in the dissolution rate of ER-34122. The solid dispersion was prepared by a solvent evaporation method using ethanol and water. The solid-state characteristics of the solid dispersion, the corresponding physical mixture, and ER-34122 alone were investigated by X-ray powder diffraction, Fourier transform infrared spectroscopy (FTIR), and an automated controlled-atmosphere microbalance. The X-ray powder diffraction patterns suggest that the solid dispersion exists in a totally amorphous state and the others exist in a crystalline state. The FTIR spectra results suggest that ER-34122 can interact with TC-5RW through intermolecular hydrogen bonding in the solid dispersion. This interaction may cause a stabilization of ER-34122 in the higher-energy, faster-dissolving amorphous state. The dissolution rate of ER-34122 from the solid dispersion was significantly greater than that from the physical mixture or the pure drug. Furthermore, when orally administrated to beagle dogs, ER-34122 showed about a 100-fold increase in both maximum concentration (Cmax) and area under the curve of concentration versus time (AUC) compared with the pure drug. Consequently, it was determined that the solid dispersion technique with TC-5RW provides a promising way to increase the dissolution rate and the oral absorption of poorly water-soluble drugs such as ER-34122. © 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:258,266, 2002 [source]


Antimalarial compounds isolated from plants used in traditional medicine

JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2009
Joanne Bero
Abstract Objectives This review covers the compounds with antiplasmodial activity isolated from plants published from 2005 to the end of 2008, organized according to their phytochemical classes. Details are given for substances with IC50 values , 11 ,M. Key findings Malaria is a major parasitic disease in many tropical and subtropical regions and is responsible for more than 1 million deaths each year in Africa. The rapid spread of resistance encourages the search for new active compounds. Nature and particularly plants used in traditional medicine are a potential source of new antimalarial drugs as they contain molecules with a great variety of structures and pharmacological activities. Summary A large number of antimalarial compounds with a wide variety of structures have been isolated from plants and can play a role in the development of new antimalarial drugs. Ethnopharmacological approaches appear to be a promising way to find plant metabolites that could be used as templates for designing new derivatives with improved properties. [source]


rpoB -PCR amplified gene and temporal temperature gradient gel electrophoresis: a rapid tool to analyse bacterial strains representative of cold-smoked salmon microflora

LETTERS IN APPLIED MICROBIOLOGY, Issue 2 2004
S. Giacomazzi
Abstract Aim:, To evaluate rpoB gene as a biomarker of microbial biodiversity associated to cold-smoked salmon by a novel nested-polymerase chain reaction/temporal temperature gradient gel electrophoresis (PCR/TTGE) technique applied on pure cultures of reference strains. Methods and Results:, DNA obtained from pure cultures of reference strains was used in a succession of a first PCR amplification of rpoB fragment with degenerated nonclamped primers and a nested-PCR with nondegenerated clamped primers. PCR products were then applied on a TTGE gel in order to analyse strains profile. High quantity of nested-PCR products were obtained for each tested strain and TTGE profiles showed a good separation between the different reference bacteria and an easy way to associate one band to one species. Conclusion:, The nested-PCR/TTGE technique used in this study is a promising way of investigating bacterial community structure of cold-smoked salmon or other food matrix. Significance and Impact of the Study:, Because of its single copy state leading to single band profiles in TTGE, rpoB constitute a good potential molecular marker for further development of cold-smoked salmon biodiversity analysis. [source]


The difficult and ubiquitous problems of multiplicities

PHARMACEUTICAL STATISTICS: THE JOURNAL OF APPLIED STATISTICS IN THE PHARMACEUTICAL INDUSTRY, Issue 3 2007
Donald A. Berry
Abstract Multiplicities are ubiquitous. They threaten every inference in every aspect of life. Despite the focus in statistics on multiplicities, statisticians underestimate their importance. One reason is that the focus is on methodology for known multiplicities. Silent multiplicities are much more important and they are insidious. Both frequentists and Bayesians have important contributions to make regarding problems of multiplicities. But neither group has an inside track. Frequentists and Bayesians working together is a promising way of making inroads into this knotty set of problems. Two experiments with identical results may well lead to very different statistical conclusions. So we will never be able to use a software package with default settings to resolve all problems of multiplicities. Every problem has unique aspects. And all problems require understanding the substantive area of application. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Citizenship and The State

PHILOSOPHY COMPASS (ELECTRONIC), Issue 6 2009
M. Victoria Costa
This study surveys debates on citizenship, the state, and the bases of political stability. The survey begins by presenting the primary sense of ,citizenship' as a legal status and the question of the sorts of political communities people can belong to as citizens. (Multi)nation-states are suggested as the main site of citizenship in the contemporary world, without ignoring the existence of alternative possibilities. Turning to discussions of citizen identity, the study shows that some of the discussion is motivated by a perceived need for citizens to have a sense of political belonging, on the assumption that such a sense promotes political activity and has other personal and social benefits. But there are serious problems with the strategy of understanding the relevant sense of belonging in terms of identification with the nation-state. The study explores a more promising way to generate this sense of belonging. First, societies should function, to a sufficiently high degree, in accord with political principles of justice and democratic decision making. Second, there should be a general consensus on political principles among citizens, as well as high levels of engagement in democratic deliberation. [source]


Antivascular Tumor Eradication by Hypericin-mediated Photodynamic Therapy,

PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 5 2002
Bin Chen
ABSTRACT Photodynamic therapy (PDT) with hypericin has been shown to inhibit tumor growth in different tumor models, and tumor vascular damage was suggested to be mainly responsible for the antitumoral effect. Here, we demonstrate tumor vascular damage and its consequence on local tumor control after hypericin-mediated PDT by using both short and long drug,light intervals. Radiation-induced fibrosarcoma-1 tumors were exposed to laser light at either 0.5 or 6 h after a 5 mg/kg dose of hypericin. Tumor perfusion was monitored by fluorescein dye,exclusion assay and by Hoechst 33342 staining of functional blood vessels. Significant reduction in tumor perfusion was found immediately after both PDT treatments. A complete arrest of vascular perfusion was detected by 15 h after the 0.5 h-interval PDT, whereas well-perfused areas could still be found at this time in tumors after the 6 h-interval PDT. A histological study confirmed that primary vascular damage was involved in both PDT treatments. Tumor cells appeared intact shortly after light treatment, degenerated at later hours and became extensively pycnotic at 24 h after the 0.5 h-interval PDT. PDT under this condition led to complete tumor cure. In contrast, significant numbers of viable tumor cells, especially at the tumor periphery, were found histologically at 24 h after the 6 h-interval PDT. No tumor cure was obtained when PDT was performed at this time. Our results strongly suggest that targeting the tumor vasculature by applying short drug,light interval PDT with hypericin might be a promising way to eradicate solid tumors. [source]


The Inheritance of Chilling Tolerance in Tomato (Lycopersicon spp.)

PLANT BIOLOGY, Issue 2 2005
J. H. Venema
Abstract: During the past 25 years, chilling tolerance of the cultivated (chilling-sensitive) tomato Lycopersicon esculentum and its wild, chilling-tolerant relatives L. peruvianum and L. hirsutum (and, less intensively studied, L. chilense) has been the object of several investigations. The final aim of these studies can be seen in the increase in chilling tolerance of the cultivated genotypes. In this review, we will focus on low-temperature effects on photosynthesis and the inheritance of these traits to the offspring of various breeding attempts. While crossing L. peruvianum (,) to L. esculentum (,) so far has brought the most detailed insight with respect to physiological questions, for practical purposes, e.g., the readily cross ability, crossing programmes with L. hirsutum as pollen donor at present seem to be a promising way to achieve higher chilling-tolerant genotypes of the cultivated tomato. This perspective is due to the progress that has been made with respect to the genetic basis of chilling tolerance of Lycopersicon spp. over the past five years. [source]


A Social Psychological Approach to Enduring Rivalries

POLITICAL PSYCHOLOGY, Issue 4 2001
Cameron G. Thies
The recent scholarly work on the concept of enduring rivalries offers a promising way to examine strategic interaction among dyads of states over extended periods of time. A focus on rivalry, and on the mechanisms that provide for such interaction, may offer a way to bridge existing theories of international relations that rely exclusively on structure or process. Unfortunately, the potential for theory-building has not been fully realized because research into rivalry has tended to be inductive. This paper seeks to rectify that problem by situating the rivalry concept within a social psychological approach to international relations. The rivalry concept is appropriately located in a theoretical approach that views the international system as a social system where actors are conditioned by mechanisms of competition and socialization. [source]


The Governance of cooperatives and mutual associations: a paradox perspective

ANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 1 2004
Chris Cornforth
The theoretical literature on the governance of co-operatives is relatively undeveloped in comparison with that on corporate governance. The paper briefly reviews some of the main theoretical perspectives on corporate governance and discusses how they can be usefully extended to throw light on the governance of co-operatives and mutuals. However, taken individually these different theories are rather one dimensional, only illuminating a particular aspect of the board's role. This has lead to calls for a new conceptual framework that can help integrate the insights of these different theories. The paper argues that a paradox perspective offers a promising way forward. Contrasting the different theoretical perspectives highlights some of the important paradoxes, ambiguities and tensions that boards face. [source]


Could a diet enriched with n-3 highly unsaturated fatty acids be considered a promising way to enhance the immune defences and the resistance of Penaeid prawns to environmental stress?

AQUACULTURE RESEARCH, Issue 2 2001
L Chim
Abstract The prawn Penaeus stylirostris (Stimpson), when fed for 28 days with n-3 highly unsaturated fatty acid (HUFA)-enriched feed pellets, demonstrated an enhanced resistance to variations in environmental parameters (a decrease in temperature and salinity over a 4-day period from 28 °C to 17 °C and from 35, to 10, respectively) and an improvement in their immune defence potential, i.e. increased agglutination titre of plasma and increased respiratory burst of haemocytes. [source]


The role of microarthropods in terrestrial decomposition: a meta-analysis of 40 years of litterbag studies

BIOLOGICAL REVIEWS, Issue 3 2009
Christian Kampichler
ABSTRACT Litterbags have been utilized in soil ecology for about 50 years. They are useful because they confine organic material and thus enable the study of decomposition dynamics (mass loss and/or nutrient loss through time, colonization by soil biota) in situ, i.e. under field conditions. Researchers can easily restrict or permit access to certain size classes of soil fauna to determine their contribution to litter mass loss by choosing adequate mesh size or applying specific biocides. In particular, the mesofauna has received much attention since it comprises two very abundant and diverse microarthropod groups, the Collembola (springtails) and Acari (mites). We comprehensively searched the literature from the mid-1960s to the end of 2005 for reports on litterbag experiments investigating the role of microarthropods in terrestrial decomposition. Thirty papers reporting 101 experiments satisfied our selection criteria and were included in the database. Our meta-analysis revealed that microarthropods have a moderate but significant effect on mass loss. We discuss in detail the interactions of the microarthropod effect with study characteristics such as experimental design (e.g. number of bags, duration of experiment), type of exposed organic matter, climatic zone and land use of the study site. No publication bias was detected; however, we noticed a significant decrease in the microarthropod effect with publication year, indicating that, in the first decades of litterbag use, soil zoologists may have studied "promising" sites with a higher a priori probability of positive microarthropod effects on litter mass loss. A general weakness is that the treatments differ not only with respect to the presence or absence of microarthropods, but also with regard to mesh size (small to exclude microarthropods, wide to permit their access) or presence (to exclude microarthropods) and absence (to permit their access) of an insecticide. Consequently, the difference between the decomposition rates in the treatments is not a pure microarthropod effect but will be influenced by the additive effects of mesh size and insecticide. The relative contribution of the "true" microarthropod effect remains unknown without additional treatments controlling for the differential mesh size/insecticide effect. A meta-analysis including only those studies using different mesh size and for which the data were corrected by subtracting an estimated mesh size effect based on data from the literature yielded a significantly negative microarthropod effect on litter decomposition. These results cast doubt on the widely accepted hypothesis that microarthropods generally exert a positive effect on litter mass loss. We conclude that after 40 years of litterbag studies our knowledge on the role of microarthropods in litter mass loss remains limited and that the inclusion of a third treatment in future studies is a promising way to retain litterbags as a meaningful tool of soil biological studies. [source]


Greening from the front to the back door?

BUSINESS STRATEGY AND THE ENVIRONMENT, Issue 3 2010
A typology of chemical, resource management services
Abstract Though services and product,service systems have been promoted as a promising way towards more eco-efficient and sustainable societies, they have not turned into reality as expected. Chemical and resource management services are among the few operational examples. They aim to align the service provider's and customer's actions to reduce chemical usage and waste, improve supply chain management and increase resource efficiency. Arguably, they also create new business and higher profit margins compared with merely selling chemicals or handling industrial waste. Thus far they have been viewed as a single business model. In contrast, this study shows through the construction of five ideal types that the actual services and their focus vary. They range from the management of the chemical supply to operations, waste reduction, combined logistics services, process management, IT and other technologies. Consequently this affects the value creation, organization and environmental efficiencies of these services. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment. [source]


Quine, Davidson, and the Naturalization of Metaethics

DIALECTICA, Issue 2 2001
Robert Feleppa
Quine's ethical views typify what might seem to be natural sympathies between empiricism and ethical noncognitivism. LikeAyer, he sees a case for noncognitivism rooted in an epistemic discontinuity between ethics and science. Quine argues that the absence of genuine moral observation sentences, and thus the absence of empirical checkpoints for the resolution of theoretical disputes, renders ethics, as he terms it, "methodologically infirm" However, recent papers in this journal make clear that Quine appears to be voicing mutually incompatible commitments to both noncognitivism and cognitivism. Here I argue that Davidson's theory of interpretation offers promising ways to resolve these tensions. His constructive program fleshes out the implications of Quine's largely destructive critique of intensional semantics and contains a fairly well-articulated account of evaluative semantics, one which seems to combine cognitivist and noncognitivist elements harmoniously. Moreover, it is argued that Davidson's long-standing differences with Quine over the epistemological status Quine accords observation sentences with do not undermine Quine's metaethical critique. [source]


Sonochemical synthetic methods to produce functionalized conducting copolymers

POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 4 2010
P. Najafi Moghadam
Abstract Polyaniline (PANI) is one of the most investigated intrinsically conducting polymers. Copolymerization of aniline with aniline derivatives was considered one of the most effective and promising ways of improving the properties of PANI. In this work, firstly ethyl 3-aminobenzoate and butyl 3-aminobenzoate were synthesized from 3-aminobenzoic acid by direct esterification. Then the copolymerization of 3-amino benzoic acid, ethyl 3-aminobenzoate, and butyl 3-aminobenzoate with aniline was carried out by sonochemical polymerization in aqueous hydrochloric acid using ammonium persulfate (APS) as an initiator. The effects of variation in the molar ratio of the two monomers on chain structure, conductivity, and the redox properties of the copolymer are discussed. The prepared polymers are characterized by 1H NMR spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Thermal behavior of the prepared copolymers was studied by differential scanning calorimetry. The copolymers were doped with HCl and their conductivity was measured. Copyright © 2009 John Wiley & Sons, Ltd. [source]